Search results for: mold filling

Authors: Tomoko Fukuyama, Osamu Senbu

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Prestressed concrete is used a lot in infrastructures such as roads or bridges. However, poor grout filling and PC steel corrosion are currently major issues of prestressed concrete structures. One of the problems with nondestructive corrosion detection of PC steel is a plastic pipe which covers PC steel. The insulative property of pipe makes a nondestructive diagnosis difficult; therefore a practical technology to detect these defects is necessary for the maintenance of infrastructures. The goal of the research is a development of an electrochemical technique which enables to detect internal defects from the surface of prestressed concrete nondestructively. Ideally, the measurements should be conducted from the surface of structural members to diagnose non-destructively. In the present experiment, a prestressed concrete member is simplified as a layered specimen to simulate a current path between an input and an output electrode on a member surface. The specimens which are layered by mortar and the prestressed concrete constitution materials (steel, polyethylene, stainless steel, or galvanized steel plates) were provided to the alternating current impedance measurement. The magnitude of an applied electric field was 0.01-volt or 1-volt, and the frequency range was from 106 Hz to 10-2 Hz. The frequency spectrums of impedance, which relate to charge reactions activated by an electric field, were measured to clarify the effects of the material configurations or the properties. In the civil engineering field, the Nyquist diagram is popular to analyze impedance and it is a good way to grasp electric relaxation using a shape of the plot. However, it is slightly not suitable to figure out an influence of a measurement frequency which is reciprocal of reaction time. Hence, Bode diagram is also applied to describe charge reactions in the present paper. From the experiment results, the alternating current impedance method looks to be applicable to the insulative material measurement and eventually prestressed concrete diagnosis. At the same time, the frequency spectrums of impedance show the difference of the material configuration. This is because the charge mobility reflects the variety of substances and also the measuring frequency of the electric field determines migration length of charges which are under the influence of the electric field. However, it could not distinguish the differences of the material thickness and is inferred the difficulties of prestressed concrete diagnosis to identify the amount of an air void or a layer of corrosion product by the technique.

Keywords: capacitance, conductance, prestressed concrete, susceptance

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Authors: Hui Li, Xiongqi Pang

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In recent years, tight oil has become a hot spot for unconventional oil and gas exploration and development in the world. Dongpu Depression is a typical hydrocarbon-rich basin in the southwest of Bohai Bay Basin, in which tight sandstone oil and gas have been discovered in deep reservoirs, most of which are buried more than 3500m. The distribution and development characteristics of deep tight sandstone reservoirs need to be studied. The main source rocks in study area are dark mudstone and shale of the middle and lower third sub-member of Shahejie Formation. Total Organic Carbon (TOC) content of source rock is between 0.08-11.54%, generally higher than 0.6% and the value of S1+S2 is between 0.04–72.93 mg/g, generally higher than 2 mg/g. It can be evaluated as middle to fine level overall. The kerogen type of organic matter is predominantly typeⅡ1 andⅡ2. Vitrinite reflectance (Ro) is mostly greater than 0.6% indicating that the source rock entered the hydrocarbon generation threshold. The physical property of reservoir was poor, the most reservoir has a porosity lower than 12% and a permeability of less than 1×10⁻³μm. The rocks in this area showed great heterogeneity, some areas developed desserts with high porosity and permeability. According to SEM, thin section image, inclusion test and so on, the reservoir was affected by compaction and cementation during early diagenesis stage (44-31Ma). The diagenesis caused the tight reservoir in Huzhuangji, Pucheng, Weicheng Area while the porosity in Machang, Qiaokou, Wenliu Area was still over 12%. In the process of middle diagenesis phase stage A (31-17Ma), the reservoir porosity in Machang, Pucheng, Huzhuangji Area increased due to dissolution; after that the oil generation window of source rock was achieved for the first phase hydrocarbon charging (31-23Ma), formed the conventional oil deposition in Machang, Qiaokou, Wenliu, Huzhuangji Area and unconventional tight reservoir in Pucheng, Weicheng Area. Then came to stage B of middle diagenesis phase (17-7Ma), in this stage, the porosity of reservoir continued to decrease after the dissolution and led to a situation that the reservoirs were generally compacted. And since then, the second hydrocarbon filling has been processing since 7Ma. Most of the pools charged and formed in this procedure are tight sandstone oil reservoir. In conclusion, tight sandstone oil was formed in two patterns in Dongpu Depression, which could be concluded as ‘density fist then accumulation’ pattern and ‘accumulation fist next density’ pattern.

Keywords: accumulation process, diagenesis, dongpu depression, tight sandstone oil

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Authors: Mahdi Nasiri Tabrizi, A. Dadkhah, M. Khirkhah

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In order to study the effect of planting on yield, yield components and quality traits in bread and durum wheat varieties, a field split-plot experiment based on complete randomized design with three replications was conducted in Agricultural and Natural Resources Research Center of Razavi Khorasan located in city of Mashhad during 2013-2014. Main factor were consisted of five sowing dates (first October, fifteenth December, first March, tenth March, twentieth March) and as sub-factors consisted of different bread wheat (Bahar, Pishgam, Pishtaz, Mihan, Falat and Karim) and two durum wheat (Dena and Dehdasht). According to results of analysis variance the effect of planting date was significant on all examined traits (grain yield, biological yield, harvest index, number of grain per spike, thousands kernel weight, number of spike per square meter, plant height, the number of days to heading, the number of days to maturity, during the grain filling period, percentage of wet gluten, percentage of dry gluten, gluten index, percentage of protein). By delay in planting, majority of traits significantly decreased, except quality traits (percentage of wet gluten, percentage of dry gluten and percentage of protein). Results of means comparison showed, among planting date the highest grain yield and biological yield were related to first planting date (Octobr) with mean of production of 5/6 and 1/17 tons per hectare respectively and the highest bread quality (gluten index) with mean of 85 and percentage of protein with mean of 13% to fifth planting date also the effect of genotype was significant on all traits. The highest grain yield among of studied wheat genotypes was related to Dehdasht cultivar with an average production of 4.4 tons per hectare. The highest protein percentage and bread quality (gluten index) were related to Dehdasht cultivar with 13.4% and Falat cultivar with number of 90 respectively. The interaction between cultivar and planting date was significant on all traits and different varieties had different trend for these traits. The highest grain yield was related to first planting date (October) and Falat cultivar with an average of production of 6/7 tons per hectare while in grain yield did not show a significant different with Pishtas and Mihan cultivars also the most of gluten index (bread quality index) and protein percentage was belonged to the third planting date and Karim cultivar with 7.98 and Dena cultivar with 7.14% respectively.

Keywords: yield component, yield, planting date, cultivar, quality traits, wheat

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Authors: Tatjana Kochetkova

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This paper explores the pivotal role of environmental education, specifically outdoor education, in facilitating a psychological connection to nature among young adults. This research aims to contribute to building an empirical and conceptual basis of ecopsychology by providing a picture of psyche-nature interaction. It presents the results of the four-day connection-to-nature workshop. It intends to find out the effects of the awareness of nature on subjective well-being and perception of the meaning of life. This led to finding a battery-recharging effect of nature and the influence of nature at four levels of awareness: external physical perception, internal (bodily) sensation, emotions, and existential meaning. The research on the psychological bond of humans with the natural environment, the subject of ecopsychology, is still in its infancy. However, despite several courageous and fruitful attempts, there are still no direct answers to the fundamental questions about the way in which the natural environment influences humans and the specific role of nature in the human psyche. The urge to address this question was the primary reason for the current experiment. The methodology of this study was taken from the study of Patterson, and from White and Hendee. The methodology included a series of assignments on the perception of nature (the exercises are described in the attachment). Experiences were noted in a personal diary, which we used later for analysis. There are many trustworthy claims that contact with nature has positive effects on human subjective well-being and that it is of essential psychological and spiritual value. But, there is a need for more support and theoretical explanation for this phenomenon. As a contribution to filling these gaps, this qualitative study was conducted. The aim of this study is to explore the psychological effects of short-term awareness of wilderness on one’s subjective well-being and on one’s sense of the meaning of life. This specific study is based on the more general hypothesis that there are positive relationships between the experience of wilderness and the development of the self, feelings of community, and spiritual development. It restricted the study of the psychological effects of short term stay in nature to two variables (subjective well-being and the sense of meaning of life). The study aimed at (i) testing the hypothesis that there are positive effects of the awareness of wilderness on the subjective sense of well-being and meaning in life, (ii) understanding the nature of the psychological need for wilderness. Although there is a substantial amount of data on the psychological benefits of nature, we still lack a theory that explains the findings. The present research aims to contribute to such a theory. This is an experiment aimed specifically at the effects of nature on the sense of well-being and meaning in life.

Keywords: environmental education, psychological connection to nature, subjective well-being, symbolic meaning of nature, emotional reaction to nature, meaning of life

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Authors: Sushil Kumar Singh, Kumar Rahul, Vivek Tewarson, Sarvesh Kumar, Shobhit Kumar

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Objective: Rheumatic mitral stenosis continues to be a major public health problem in developing countries. When the left atrium (LA) is unable to fill the left ventricle (LV) at normal LA pressures due to impaired relaxation and impaired compliance, diastolic dysfunction occurs. The assessment of left ventricular (LV) diastolic function and filling pressures is of clinical importance to identify underlying cardiac disease, its treatment, and to assess prognosis. 2D echocardiography can detect diastolic dysfunction with excellent sensitivity and minimal risk when compared to the gold standard of invasive pressure-volume measurements. Material and Method: This was a one-year study consisting of twenty-nine patients of isolated rheumatic severe mitral stenosis. Data was analyzed preoperative and post operative (at one month follow-up). Transthoracic 2D echocardiographic parameters of the diastolic function are transmitral flow, pulmonary venous flow, mitral annular tissue doppler, and color M-mode doppler. In our study, mitral valve orifice area, ejection fraction, deceleration time, E/A-wave, E/E’-wave, myocardial performance index of left ventricle (Tei index ), and Mitral inflow propagation velocity were included for echocardiographic evaluation. The statistical analysis was performed on SPSS Version 15.0 statistical analysis software. Result: Twenty-nine patients underwent successful closed mitral commissurotomy for isolated mitral stenosis. The outcome measures were observed pre-operatively and at one-month follow-up. The majority of patients were in NYHA grade III (69.0%) in the preoperative period, which improved to NYHA grade I (48.3%) after closed mitral commissurotomy. Post-surgery mitral valve area increased from 0.77 ± 0.13 to 2.32 ± 0.26 cm, ejection fraction increased from 61.38 ± 4.61 to 64.79 ± 3.22. There was a decrease in deceleration time from 231.55 ± 49.31 to 168.28 ± 14.30 ms, E/A ratio from 1.70 ± 0.54 from 0.89 ± 0.39, E/E’ ratio from 14.59 ± 3.34 to 8.86 ± 3.03. In addition, there was improvement in TIE index from 0.50 ± 0.03 to 0.39 ± 0.06 and mitral inflow propagation velocity from 47.28 ± 3.71 to 57.86 ± 3.19 cm/sec. In peri-operative and follow-up, there was no incidence of severe mitral regurgitation (MR). There was no thromboembolic incident and no mortality.

Keywords: closed mitral valvotomy, mitral stenosis, open mitral commissurotomy, balloon mitral valvotomy

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Authors: L. U. Dumuje, R. Leite

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There is an ongoing debate in terms of corporate social responsibility (CSR) initiative in Niger Delta, Nigeria, that originates from existing gap between stated objective of organizations in the Nigerian oil sector and their main activities that threaten the society. CSR in developing countries is becoming popular, and to contribute to scientific knowledge, we need to research on CSR practices and discourse in indigenous Nigeria that is scarce. Despite governments mandate in terms of unofficial blazing, methane gas is released into the air around refinery area which contributes to global warming. There is a need to understand if this practice applies to indigenous oil companies in Nigeria. To get a better understanding of CSR among indigenous oil companies in Nigeria, our study focuses on discourse and rhetoric regarding CSR. This current paper contributions is twofold: on the one hand, it aims to better understand practitioner’s rationale and fundamentals of CSR in Nigerian oil companies. On the other hand, it intends to identify the stages of CSR initiatives, advantages and difficulties of CSR implementation in indigenous Nigeria oil sector. This current paper uses the qualitative research as a methodological strategy. Instrument for data collection is semi-structured interview. Besides 28 interviews, we conduct five focus group discussions with stakeholders. Participant for this study consist of: employees, managers and executives of indigenous oil companies in Nigeria. It is relevant to mention, key informants as government institution, environmental organization and community leader/member are part of our sample. It is important that despite significant findings in some studies, there are still some gaps. To help filling this existing gaps, we have formulated some research questions, as follows: ‘What are the stages, opportunities and obstacles of having corporate social responsibility practice in indigenous oil companies in Nigeria’. This ongoing research sub-questions as follows: What are the CSR discourses and practices among indigenous companies in the Nigerian oil sector; what is the actual status regarding CSR development; what are the main perceptions of opportunities and obstacles with regard to CSR in indigenous Nigerian oil companies; who are the main stakeholders of indigenous Nigerian oil companies and their different meanings and understandings of CSR practices. Regarding the above questions, the following objectives have been determined: first, we conduct a literature review with the aim of understanding and identifying importance of CSR practises in western and developing countries. Second, this current paper identify specific characteristics of the national context in terms of CSR engagement in Nigeria, so we perform empirical research with relevant stakeholder in indigenous Nigerian, as well as key informants, in order to identify development of CSR and different perception of this praised initiative, CSR.

Keywords: corporate social responsibility, indigenous, oil organizations, Nigeria, practice

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Authors: Mónika Ditta Tóth, Ádám Fritz, Balázs Hankó, György Purebl

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Communication training about depression and suicide prevention for pharmacists – A Hungarian pilot study Mónika Ditta Tóth1, Ádám Fritz2, Balázs Hankó2, György Purebl1 1: Semmelweis University, Institute of Behavioural Sciences 2: Semmelweis University, University Pharmacy Department of Pharmacy Administration Background: Suicide rates in Hungary have been one of the highest in the European Union. Depression is one of the main risk factors for suicide and recognizing and treating depression is an effective way to prevent suicidal behaviour. In their daily practice, pharmacists meet patients with high risk of mental health problems. Therefore they have a key role in the prevention of depression and suicide. Aim: The main aim of this study is to raise pharmacists’ awareness about depression and suicide to enable better recognation of verbal and non-verbal signs of these deseases. Another important objective is to reduce their stigma about depression and increase their confidence in communication with depressed and/or suicidal patients. Methods: A 3-hour communication workshop has been delivered in this pilot study about the reasons, trigger factors, verbal and non-verbal signs of depression and suicide. The training includes communication techniques which have been developed to patients needs, as well as role-playing scenarios. Depression Stigma and Morris Confidence Scales were applied before, after and 6 weeks following the training. The results of the training group are then compared with two of the following pharmacist groups: 1. written material only (N=15), 2. no material (N=15). Results: One-way ANOVA revealed significant differences in the training group regarding the level of confidence in treating and communicating with patients with depression and/or suicide following the training, and after 6 weeks (F(2, 24)= 7,135, p=,004; baseline: 20,37, after training: 30,00, follow up: 27,66). After the 3-hour workshop the personal stigma about depression decreased (baselin: 19,75 after training: 17,00, p=0,075) in the training group (N=9), whilst the perceived stigma did not change (before: 33.54, after: 33,44, p=NS). Trainees assessed the workshop as ‘useful’ and ‘gap filling’. No significant differences was found in the group of pharmacisists who got written material only. Conclusions: Despite the high rates of depression and suicide in Hungary, pharmacists do not receive lectures or seminars about mental health during their university studies. Such half-day workshops could fill this gap and give practical help to recognize and communicate with depressed and/or suicidal patients in a more effective way. This way pharmacists, as community gate-keepers, could contribute to a more effective suicide prevention program in Hungary.

Keywords: communication training, pharmacists, depression, suicide

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Authors: Paul Holmes, Mike N. G.

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Foundation-year doctors face increased stress, pressure and uncertainty when starting new rotations throughout their first years of work. This research questionnaire resulted in an induction cheat sheet and induction video that enhanced the Junior doctor's understanding of how to work effectively within the plastic surgery department at NHS Tayside. The objectives and goals were to improve the transition between cohorts of junior doctors in ward 26 at Ninewells Hospital. Before this quality improvement project, the induction pack was 74 pages long and over eight years old. With the support of consultant Mike Ng a new up-to-date induction was created. This involved a questionnaire and cheat sheet being developed. The questionnaire covered clerking, venipuncture, ward pharmacy, theatres, admissions, specialties on the ward, the cardiac arrest trolley, clinical emergencies, discharges and escalation. This audit has three completed cycles between August 2022 and August 2023. The cheat sheet developed a concise two-page A4 document designed for doctors to be able to reference easily and understand the essentials. The document format is a table containing ward layout; specialty; location; physician associate, shift patterns; ward rounds; handover location and time; hours coverage; senior escalation; nights; daytime duties, meetings/MDTs/board meetings, important bleeps and codes; department guidelines; boarders; referrals and patient stream; pharmacy; absences; rota coordinator; annual leave; top tips. The induction video is a 10-minute in-depth explanation of all aspects of the ward. The video explores in more depth the contents of the cheat sheet. This alternative visual format familiarizes the junior doctor with all aspects of the ward. These were provided to all foundation year 1 and 2 doctors on ward 26 at Ninewells Hospital at NHS Tayside Scotland. This work has since been adopted by the General Surgery Department, which extends to six further wards and has improved the effective handing over of the junior doctor’s role between cohorts. There is potential to further expand the cheat sheet to other departments as the concise document takes around 30 minutes to complete by a doctor who is currently on that ward. The time spent filling out the form provides vital information to the incoming junior doctors, which has a significant possibility to improve patient care.

Keywords: induction, junior doctor, handover, plastic surgery

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Authors: Eun Mi Ryu, Ah Young An, Ji Yeon Kang, Yeong Soo Shin, Hee Sun Kim

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As the number of fire incidents has been increased, fire incidents significantly damage economy and human lives. Especially when high strength reinforced concrete is exposed to high temperature due to a fire, deterioration occurs such as loss in strength and elastic modulus, cracking, and spalling of the concrete. Therefore, it is important to understand risk of structural safety in building structures by studying structural behaviors and rehabilitation of fire damaged high strength concrete structures. This paper aims at investigating rehabilitation effect on fire damaged high strength concrete beams using experimental and analytical methods. In the experiments, flexural specimens with high strength concrete are exposed to high temperatures according to ISO 834 standard time temperature curve. After heated, the fire damaged reinforced concrete (RC) beams having different cover thicknesses and fire exposure time periods are rehabilitated by removing damaged part of cover thickness and filling polymeric mortar into the removed part. From four-point loading test, results show that maximum loads of the rehabilitated RC beams are 1.8~20.9% higher than those of the non-fire damaged RC beam. On the other hand, ductility ratios of the rehabilitated RC beams are decreased than that of the non-fire damaged RC beam. In addition, structural analyses are performed using ABAQUS 6.10-3 with same conditions as experiments to provide accurate predictions on structural and mechanical behaviors of rehabilitated RC beams. For the rehabilitated RC beam models, integrated temperature–structural analyses are performed in advance to obtain geometries of the fire damaged RC beams. After spalled and damaged parts are removed, rehabilitated part is added to the damaged model with material properties of polymeric mortar. Three dimensional continuum brick elements are used for both temperature and structural analyses. The same loading and boundary conditions as experiments are implemented to the rehabilitated beam models and nonlinear geometrical analyses are performed. Structural analytical results show good rehabilitation effects, when the result predicted from the rehabilitated models are compared to structural behaviors of the non-damaged RC beams. In this study, fire damaged high strength concrete beams are rehabilitated using polymeric mortar. From four point loading tests, it is found that such rehabilitation is able to make the structural performance of fire damaged beams similar to non-damaged RC beams. The predictions from the finite element models show good agreements with the experimental results and the modeling approaches can be used to investigate applicability of various rehabilitation methods for further study.

Keywords: fire, high strength concrete, rehabilitation, reinforced concrete beam

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Authors: M. De Filippo, J. S. Kuang

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In construction industry, reinforced concrete (RC) slabs represent fundamental elements of buildings and bridges. Different methods are available for analysing the structural behaviour of slabs. In the early ages of last century, the yield-line method has been proposed to attempt to solve such problem. Simple geometry problems could easily be solved by using traditional hand analyses which include plasticity theories. Nowadays, advanced finite element (FE) analyses have mainly found their way into applications of many engineering fields due to the wide range of geometries to which they can be applied. In such cases, the application of an elastic or a plastic constitutive model would completely change the approach of the analysis itself. Elastic methods are popular due to their easy applicability to automated computations. However, elastic analyses are limited since they do not consider any aspect of the material behaviour beyond its yield limit, which turns to be an essential aspect of RC structural performance. Furthermore, their applicability to non-linear analysis for modeling plastic behaviour gives very reliable results. Per contra, this type of analysis is computationally quite expensive, i.e. not well suited for solving daily engineering problems. In the past years, many researchers have worked on filling this gap between easy-to-implement elastic methods and computationally complex plastic analyses. This paper aims at proposing a numerical procedure, through which a pseudo-lower bound solution, not violating the yield criterion, is achieved. The advantages of moment distribution are taken into account, hence the increase in strength provided by plastic behaviour is considered. The lower bound solution is improved by detecting over-yielded moments, which are used to artificially rule the moment distribution among the rest of the non-yielded elements. The proposed technique obeys Nielsen’s yield criterion. The outcome of this analysis provides a simple, yet accurate, and non-time-consuming tool of predicting the lower-bound solution of the collapse load of RC slabs. By using this method, structural engineers can find the fracture patterns and ultimate load bearing capacity. The collapse triggering mechanism is found by detecting yield-lines. An application to the simple case of a square clamped slab is shown, and a good match was found with the exact values of collapse load.

Keywords: computational mechanics, lower bound method, reinforced concrete slabs, yield-line

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Authors: Viktor D. Dubrovin, Masoud Mollaee, Jie Zong, Xiushan Zhu, Nasser Peyghambarian

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Glasses doped with high rare-earth (RE) elements concentration attracted considerable attention since the middle of the 20th century due to their particular magneto-optical properties. Such glasses exhibit the Faraday effect in which the polarization plane of a linearly polarized light beam is rotated by the interaction between the incident light and the magneto-optical material. That effect found application in optical isolators that are useful for laser systems, which can prevent back reflection of light into lasers or optical amplifiers and reduce signal instability and noise. Glasses are of particular interest since they are cost-effective and can be formed into fibers, thus breaking the limits of traditional bulk optics requiring optical coupling for use with fiber-optic systems. The advent of high-power fiber lasers operating near 2µm revealed a necessity in the development of all fiber isolators for this region. Ce³⁺, Pr³⁺, Dy³⁺, and Tb³⁺ ions provide the biggest contribution to the Verdet constant value of optical materials among the RE. It is known that Pr³⁺ and Tb³⁺ ions have strong absorption bands near 2 µm, thus making Dy³⁺ and Ce³⁺ the only prospective candidates for fiber isolator operating in that region. Due to the high tendency of Ce³⁺ ions pass to Ce⁴⁺ during the synthesis, glasses with high cerium content usually suffers from Ce⁴⁺ ions absorption extending from visible to IR. Additionally, Dy³⁺ (₆H¹⁵/²) same as Ho³⁺ (⁵I₈) ions, have the largest effective magnetic moment (µeff = 10.6 µB) among the RE ions that starts to play the key role if the operating region is far from 4fⁿ→ 4fⁿ⁻¹5 d¹ electric-dipole transition relevant to the Faraday Effect. Considering the high effective magnetic moment value of Er³⁺ ions (µeff = 9.6 µB) that is 3rd after Dy³⁺/ Ho³⁺ and Tb³⁺, it is possible to assume that Er³⁺ doped glasses should exhibit Verdet constant value near 2µm that is comparable with one of Dy doped glasses. Thus, partial replacement of Dy³⁺ on Er³⁺ ions has been performed, keeping the overall concentration of Re₂O₃ equal to 70 wt.% (30.6 mol.%). Al₂O₃-B₂O₃-SiO₂-30.6RE₂O₃ (RE= Er, Dy) glasses had been synthesized, and their thermal, spectral, optical, structural, and magneto-optical properties had been studied. Glasses synthesis had been conducted in Pt crucibles for 3h at 1500 °C. The obtained melt was poured into preheated up to 400 °C mold and annealed from 800 oC to room temperature for 12h with 1h dwell. The mass of obtained glass samples was about 200g. Shown that the difference between crystallization and glass transition temperature is about 150 oC, even taking into account the fact that high content of RE₂O₃ leads to glass network depolymerization. Verdet constant of Al₂O₃-B₂O₃-SiO₂-30.6RE₂O₃ glasses for wavelength 1950 nm can reach more than 5.9 rad/(T*m), which is among the highest number reported for a paramagnetic glass at this wavelength. The refractive index value was found to be equal to 1.7545 at 633 nm. Our experimental results show that Al₂O₃-B₂O₃-SiO₂-30.6RE₂O₃ glasses with high Dy₂O₃ content are expected to be promising material for use as highly effective Faraday isolators and modulators of electromagnetic radiation in the 2μm region.

Keywords: oxide glass, magneto-optical, dysprosium, erbium, Faraday rotator, boron-aluminosilicate system

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Authors: Sabri Serkan Gulluoglu

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The study is aimed at examining the effects of internet marketing with IPTV on human beings. Internet marketing with IPTV is emerging as an integral part of business strategies in today’s technologically advanced world and the business activities all over the world are influences with the emergence of this modern marketing tool. As the population of the Internet and on-line users’ increases, new research issues have arisen concerning the demographics and psychographics of the on-line user and the opportunities for a product or service. In recent years, we have seen a tendency of various services converging to the ubiquitous Internet Protocol based networks. Besides traditional Internet applications such as web browsing, email, file transferring, and so forth, new applications have been developed to replace old communication networks. IPTV is one of the solutions. In the future, we expect a single network, the IP network, to provide services that have been carried by different networks today. For finding some important effects of a video based technology market web site on internet, we determine to apply a questionnaire on university students. Recently some researches shows that in Turkey the age of people 20 to 24 use internet when they buy some electronic devices such as cell phones, computers, etc. In questionnaire there are ten categorized questions to evaluate the effects of IPTV when shopping. There were selected 30 students who are filling the question form after watching an IPTV channel video for 10 minutes. This sample IPTV channel is “buy.com”, it look like an e-commerce site with an integrated IPTV channel on. The questionnaire for the survey is constructed by using the Likert scale that is a bipolar scaling method used to measure either positive or negative response to a statement (Likert, R) it is a common system that is used is the surveys. By following the Likert Scale “the respondents are asked to indicate their degree of agreement with the statement or any kind of subjective or objective evaluation of the statement. Traditionally a five-point scale is used under this methodology”. For this study also the five point scale system is used and the respondents were asked to express their opinions about the given statement by picking the answer from the given 5 options: “Strongly disagree, Disagree, Neither agree Nor disagree, Agree and Strongly agree”. These points were also rates from 1-5 (Strongly disagree, Disagree, Neither disagree Nor agree, Agree, Strongly agree). On the basis of the data gathered from the questionnaire some results are drawn in order to get the figures and graphical representation of the study results that can demonstrate the outcomes of the research clearly.

Keywords: IPTV, internet marketing, online, e-commerce, video based technology

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Authors: Hannele Kuusisto, Paivi Makila, Ursula Hyrkkanen

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Introduction: There have been arguments about the skills university students should have when graduated. Current trends argue that as well as the specific job-related skills the graduated students need problem-solving, interaction and networking skills as well as self-management skills. Skills required in working life are also considered in the Finnish national project called VALTE (short for 'prepared for working life'). The project involves 11 Finnish school organizations. As one result of this project, a five-credit independent online course in study and job engagement as well as in study and job crafting was developed at Turku University of Applied Sciences. The aim of the oral or e-poster presentation is to present the online course developed in the project. The purpose of this abstract is to present the development work of the online course and the feedback received from the pilots. Method: As the University of Turku is the leading partner of the VALTE project, the collaborative education platform ViLLE (https://ville.utu.fi, developed by the University of Turku) was chosen as the online platform for the course. Various exercise types with automatic assessment were used; for example, quizzes, multiple-choice questions, classification exercises, gap filling exercises, model answer questions, self-assessment tasks, case tasks, and collaboration in Padlet. In addition, the free material and free platforms on the Internet were used (Youtube, Padlet, Todaysmeet, and Prezi) as well as the net-based questionnaires about the study engagement and study crafting (made with Webropol). Three teachers with long teaching experience (also with job crafting and online pedagogy) and three students working as trainees in the project developed the content of the course. The online course was piloted twice in 2017 as an elective course for the students at Turku University of Applied Sciences, a higher education institution of about 10 000 students. After both pilots, feedback from the students was gathered and the online course was developed. Results: As the result, the functional five-credit independent online course suitable for students of different educational institutions was developed. The student feedback shows that students themselves think that the developed online course really enhanced their job and study crafting skills. After the course, 91% of the students considered their knowledge in job and study engagement as well as in job and study crafting to be at a good or excellent level. About two-thirds of the students were going to exploit their knowledge significantly in the future. Students appreciated the variability and the game-like feeling of the exercises as well as the opportunity to study online at the time and place they chose themselves. On a five-point scale (1 being poor and 5 being excellent), the students graded the clarity of the ViLLE platform as 4.2, the functionality of the platform as 4.0 and the easiness of operating as 3.9.

Keywords: job crafting, job engagement, online course, study crafting, study engagement

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Authors: Apeng Dong, Shu Li, Wenguo Zhu, Ming Qi, Qiuyi Xu

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The primary objective of this paper is to focus on the elasticity properties of three-dimensional full five directional (3Df5d) braided composite. A large body of research has been focused on the 3D four directional (4d) and 3D five directional (5d) structure but not much research on the 3Df5d material. Generally, the influence of the yarn shape on mechanical properties of braided materials tends to be ignored, which makes results too ideal. Besides, with the improvement of the computational ability, people are accustomed to using computers to predict the material parameters, which fails to give an explicit and concise result facilitating production and application. Based on the traditional mechanics, this paper firstly deduced the functional relation between elasticity properties and braiding parameters. In addition, considering the actual shape of yarns after consolidation, the longitudinal modulus is modified and defined practically. Firstly, the analytic model is established based on the certain assumptions for the sake of clarity, this paper assumes that: A: the cross section of axial yarns is square; B: The cross section of braiding yarns is hexagonal; C: the characters of braiding yarns and axial yarns are the same; D: The angle between the structure boundary and the projection of braiding yarns in transverse plane is 45°; E: The filling factor ε of composite yarns is π/4; F: The deformation of unit cell is under constant strain condition. Then, the functional relation between material constants and braiding parameters is systematically deduced aimed at the yarn deformation mode. Finally, considering the actual shape of axial yarns after consolidation, the concept of technology factor is proposed and the longitudinal modulus of the material is modified based on the energy theory. In this paper, the analytic solution of material parameters is given for the first time, which provides a good reference for further research and application for 3Df5d materials. Although the analysis model is established based on certain assumptions, the analysis method is also applicable for other braided structures. Meanwhile, it is crucial that the cross section shape and straightness of axial yarns play dominant roles in the longitudinal elastic property. So in the braiding and solidifying process, the stability of the axial yarns should be guaranteed to increase the technology factor to reduce the dispersion of material parameters. Overall, the elastic properties of this materials are closely related to the braiding parameters and can be strongly designable, and although the longitudinal modulus of the material is greatly influenced by the technology factors, it can be defined to certain extent.

Keywords: analytic solution, braided composites, elasticity properties, technology factor

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Authors: Petru Urdea

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As a distinct part of the mountain system, the rock glacier system is a particularly periglacial debris system. Being an open system, it works in a manner of interconnection with others subsystems like glacial, cliffs, rocky slopes sand talus slope subsystems, which are sources of sediments. One characteristic is that for long periods of time it is like a storage unit for debris, and ice, and temporary for snow and water. In the Southern Carpathians 306 rock glaciers were identified. The vast majority of these rock glaciers, are talus rock glaciers, 74%, and 26%, are debris rock glaciers. In the area occupied by granites and granodiorites are present, 49% of all the rock glaciers, representing 61% of the area occupied by Southern Carpathians rock glaciers. This lithological dependence also leaves its mark on the specifics of the deposits, everything bearing the imprint of the particular way the rocks respond to the physical weathering processes, all in a periglacial regime. If in the domain of granites and granodiorites the blocks are large, - of metric order, even 10 m3 - , in the domain of the metamorphic rocks only gneisses can cut similar sizes. Amphibolites, amphibolitic schists, micaschists, sericite-chlorite schists and phyllites crop out in much smaller blocks, of decimetric order, mostly in the form of slabs. In the case of rock glaciers made up of large blocks, with a strcture of open-works type, the density and volume of voids between the blocks is greater, the smaller debris generating more compact structures with fewer voids. All these influences the thermal regime, associated with a certain type of air circulation during the seasons and the emergence of permafrost formation conditions. The rock glaciers are fed by rock falls, rock avalanches, debris flows, avalanches, so that the structure is heterogeneous, which is also reflected in the detailed topography of the rock glaciers. This heterogeneity is also influenced by the spatial assembly of the rock bodies in the supply area and, an element that cannot be omitted, the behavior of the rocks during periglacial weathering. The production of small gelifracts determines the filling of voids and the appearance of more compact structures, with effects on the creep process. In general, surface deposits are coarser, those in depth are finer, their characteristics being detectable by applying geophysical methods. The electrical tomography (ERT) and georadar (GPR) investigations carried out in the Făgăraş Mountains, Retezat and the Parâng Mountains, each with a different lithological specificity, allowed the identification of some differentiations, including the presence of permafrost bodies.

Keywords: rock glaciers deposits, structure, lithology, permafrost, Southern Carpathians, Romania

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Authors: Bambang Antoro, Lasito Soebari, Geoffrey de Jong, Fernandy Meiriyanto, Michael Siahaan, Eko Wibowo, Pormando Silalahi, Ruswanto, Adi Budirumantyo

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The Ertsberg East Skarn System (EESS) is located in the Ertsberg Mining District, Papua, Indonesia. EESS is a sub-vertical zone of copper-gold mineralization hosted in both diorite (vein-style mineralization) and skarn (disseminated and vein style mineralization). Deep Mill Level Zone (DMLZ) is a mining zone in the lower part of East Ertsberg Skarn System (EESS) that product copper and gold. The Deep Mill Level Zone deposit is located below the Deep Ore Zone deposit between the 3125m to 2590m elevation, measures roughly 1,200m in length and is between 350 and 500m in width. DMLZ planned start mined on Q2-2015, being mined at an ore extraction rate about 60,000 tpd by the block cave mine method (the block cave contain 516 Mt). Mineralization and associated hydrothermal alteration in the DMLZ is hosted and enclosed by a large stock (The Main Ertsberg Intrusion) that is barren on all sides and above the DMLZ. Late porphyry dikes that cut through the Main Ertsberg Intrusion are spatially associated with the center of the DMLZ hydrothermal system. DMLZ orebody hosted in diorite and skarn, both dominantly by vein style mineralization. Percentage Material Mined at DMLZ compare with current Reserves are diorite 46% (with 0.46% Cu; 0.56 ppm Au; and 0.83% EqCu); Skarn is 39% (with 1.4% Cu; 0.95 ppm Au; and 2.05% EqCu); Hornfels is 8% (with 0.84% Cu; 0.82 ppm Au; and 1.39% EqCu); and Marble 7 % possible mined waste. Correlation between Ertsberg intrusion, major structure, and vein style mineralization is important to determine characteristic orebody in DMLZ Mine. Generally Deep Mill Level Zone has 2 type of vein filling mineralization from both hosted (diorite and skarn), in diorite hosted the vein system filled by chalcopyrite-bornite-quartz and pyrite, in skarn hosted the vein filled by chalcopyrite-bornite-pyrite and magnetite without quartz. Based on orientation the stockwork vein at diorite hosted and shallow vein in skarn hosted was generally NW-SE trending and NE-SW trending with shallow-moderate dipping. Deep Mill Level Zone control by two main major faults, geologist founded and verified local structure between major structure with NW-SE trending and NE-SW trending with characteristics slickenside, shearing, gauge, water-gas channel, and some has been re-healed.

Keywords: copper-gold, DMLZ, skarn, structure

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Authors: Piret Pernik

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Based on strategic, operational, and technical analysis of the ongoing armed conflict in Ukraine, this paper will examine the opportunities and risks of using small commercial drones (dual-use unmanned aerial vehicles, UAV) for military purposes. The paper discusses the opportunities and risks in the information domain, encompassing both cyber and electromagnetic interference and attacks. The paper will draw conclusions on a possible strategic impact to the battlefield outcomes in the modern armed conflicts by the widespread use of dual-use UAVs. This article will contribute to filling the gap in the literature by examining based on empirical data cyberattacks and electromagnetic interference. Today, more than one hundred states and non-state actors possess UAVs ranging from low cost commodity models, widely are dual-use, available and affordable to anyone, to high-cost combat UAVs (UCAV) with lethal kinetic strike capabilities, which can be enhanced with Artificial Intelligence (AI) and Machine Learning (ML). Dual-use UAVs have been used by various actors for intelligence, reconnaissance, surveillance, situational awareness, geolocation, and kinetic targeting. Thus they function as force multipliers enabling kinetic and electronic warfare attacks and provide comparative and asymmetric operational and tactical advances. Some go as far as argue that automated (or semi-automated) systems can change the character of warfare, while others observe that the use of small drones has not changed the balance of power or battlefield outcomes. UAVs give considerable opportunities for commanders, for example, because they can be operated without GPS navigation, makes them less vulnerable and dependent on satellite communications. They can and have been used to conduct cyberattacks, electromagnetic interference, and kinetic attacks. However, they are highly vulnerable to those attacks themselves. So far, strategic studies, literature, and expert commentary have overlooked cybersecurity and electronic interference dimension of the use of dual use UAVs. The studies that link technical analysis of opportunities and risks with strategic battlefield outcomes is missing. It is expected that dual use commercial UAV proliferation in armed and hybrid conflicts will continue and accelerate in the future. Therefore, it is important to understand specific opportunities and risks related to the crowdsourced use of dual-use UAVs, which can have kinetic effects. Technical countermeasures to protect UAVs differ depending on a type of UAV (small, midsize, large, stealth combat), and this paper will offer a unique analysis of small UAVs both from the view of opportunities and risks for commanders and other actors in armed conflict.

Keywords: dual-use technology, cyber attacks, electromagnetic warfare, case studies of cyberattacks in armed conflicts

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Authors: Szymon Kuczynski, Krystian Liszka, Mariusz Laciak, Andrii Oliinyk, Adam Szurlej

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The history of gaseous fuel use in the motive power of vehicles dates back to the second half of the nineteenth century, and thus the beginnings of the automotive industry. The engines were powered by coal gas and became the prototype for internal combustion engines built so far. It can thus be considered that this construction gave rise to the automotive industry. As the socio-economic development advances, so does the number of motor vehicles. Although, due to technological progress in recent decades, the emissions generated by internal combustion engines of cars have been reduced, a sharp increase in the number of cars and the rapidly growing traffic are an important source of air pollution and a major cause of acoustic threat, in particular in large urban agglomerations. One of the solutions, in terms of reducing exhaust emissions and improving air quality, is a more extensive use of alternative fuels: CNG, LNG, electricity and hydrogen. In the case of electricity use for transport, it should be noted that the environmental outcome depends on the structure of electricity generation. The paper shows selected regulations affecting the use of alternative fuels for transport (including Directive 2014/94/EU) and its dynamics between 2000 and 2015 in Poland and selected EU countries. The paper also gives a focus on the impact of alternative fuels on the environment by comparing the volume of individual emissions (compared to the emissions from conventional fuels: petrol and diesel oil). Bearing in mind that the extent of various alternative fuel use is determined in first place by economic conditions, the article describes the price relationships between alternative and conventional fuels in Poland and selected EU countries. It is pointed out that although Poland has a wealth of experience in using methane alternative fuels for transport, one of the main barriers to their development in Poland is the extensive use of LPG. In addition, a poorly developed network of CNG stations in Poland, which does not allow easy transport, especially in the northern part of the country, is a serious problem to a further development of CNG use as fuel for transport. An interesting solution to this problem seems to be the use of home CNG filling stations: Home Refuelling Appliance (HRA, refuelling time 8-10 hours) and Home Refuelling Station (HRS, refuelling time 8-10 minutes). The team is working on HRA and HRS technologies. The article also highlights the impact of alternative fuel use on energy security by reducing reliance on imports of crude oil and petroleum products.

Keywords: alternative fuels, CNG (Compressed Natural Gas), CNG stations, LNG (Liquefied Natural Gas), NGVs (Natural Gas Vehicles), pollutant emissions

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Authors: Laura Dumuje

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The ongoing debate in terms of corporate social responsibility (CSR) initiative in Niger Delta originates from existing gap between stated objectives of organizations in the Nigerian oil sector and the activities that threaten the economy. CSR in developing countries is becoming popular, and to contribute to scientific knowledge, we need to research on CSR practices and discourse in indigenous Nigeria that is scarce. Despite governments mandate in terms of unofficial gas blazing, methane is being released into the atmosphere which contributes to global warming. Does this practice apply to indigenous companies? In this context, we need to investigate CSR policies in local Nigeria. To get a better understanding of CSR among indigenous oil companies in Nigeria, our study focuses on discourse and rhetoric in terms of CSR, as well as growth regarding CSR. This current study contribution is twofold: on the one hand, it aims to better understand practitioner’s rationale and fundamentals of CSR in Nigerian oil companies. On the other hand, it intends to identify the stages of CSR initiatives, advantages and difficulties of CSR implementation in indigenous Nigeria oil sector. This study will use the qualitative research as methodological strategy. Instrument for data collection is semi-structured interview. Besides interview, we will conduct some focus group discussions with relevant stakeholders. Participants for this study consist of employees, managers and top level executives of indigenous oil companies in Nigeria. Key informants such as government institutions, environmental organizations and community leaders will take part of our samples. It is important to note that despite significant findings in some studies, there are still some gaps. To help filling this existing gaps, we have formulated some research questions, as follows: ‘What are the stages, opportunities and obstacles of having corporate social responsibility practice in indigenous oil companies in Nigeria?’ This ongoing research sub-questions as follows: What are the CSR discourses and practices among indigenous companies in the Nigerian oil sector? What is the actual status regarding CSR development? What are the main perceptions of opportunities and obstacles with regard to CSR in indigenous Nigerian oil companies? Who are the main stakeholders of indigenous Nigerian oil companies and their different meanings and understandings of CSR practices? Important to note regarding the above questions, the following objectives have been determined: This research conducts a literature review with the aim of uncovering, understanding and identifying importance of CSR practices in western and developing countries; It aims to identify specific characteristics of the national context in respect to CSR engagement in Nigeria; Relevant to perform empirical research with employees, managers, executives, and key informants in indigenous Nigerian oil companies in order to identify different understandings of CSR initiatives and its relevance to the society; To conclude, provide managerial recommendations regarding the adoption of CSR in Nigeria.

Keywords: corporate social responsibility, indigenous, organization, Nigeria

Procedia PDF Downloads 179

Authors: Ekaterina G. Lipatova

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The developing potential of a video task in teaching foreign languages involves the opportunities to improve four aspects of speech production process: listening, reading, speaking and writing. A video represents the sequence of actions, realized in the pictures logically connected and verbalized speech flow that simplifies and stimulates the process of perception. In this connection listening skills of students are developed effectively as well as their intellectual properties such as synthesizing, analyzing and generalizing the information. In terms of teaching capacity, a video task, in our opinion, is more stimulating than a traditional listening, since it involves the student into the plot of the communicative situation, emotional background and potentially makes them react to the gist in the cognitive and communicative ways. To be an effective method of teaching the video task should be structured in the way of psycho-linguistic characteristics of speech production process, in other words, should include three phases: before-watching, while-watching and after-watching. The system of tasks provided to each phase might involve the situations on reflecting to the video content in the forms of filling-the-gap tasks, multiple choice, True-or-False tasks (reading skills), exercises on expressing the opinion, project fulfilling (writing and speaking skills). In the before-watching phase we offer the students to adjust their perception mechanism to the topic and the problem of the chosen video by such task as “what do you know about such a problem?”, “is it new for you?”, “have you ever faced the situation of…?”. Then we proceed with the lexical and grammatical analysis of language units that form the body of a speech sample to lessen the perception and develop the student’s lexicon. The goal of while-watching phase is to build the student’s awareness about the problem presented in the video and challenge their inner attitude towards what they have seen by identifying the mistakes in the statements about the video content or making the summary, justifying their understanding. Finally, we move on to development of their speech skills within the communicative situation they observed and learnt by stimulating them to search the similar ideas in their backgrounds and represent them orally or in the written form or express their own opinion on the problem. It is compulsory to highlight, that a video task should contain the urgent, valid and interesting event related to the future profession of the student, since it will help to activate cognitive, emotional, verbal and ethic capacity of students. Also, logically structured video tasks are easily integrated into the system of e-learning and can provide the opportunity for the students to work with the foreign language on their own.

Keywords: communicative situation, perception mechanism, speech production process, speech skills

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Authors: Chunhua Liao, Jinfei Wang, Bo Shan, Yang Song, Yongjun He, Taifeng Dong

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Winter wheat is one of the main crops in Canada. Forecasting of within-field variability of yield in winter wheat at the early stages is essential for precision farming. However, the crop yield modelling based on high spatial resolution satellite data is generally affected by the lack of continuous satellite observations, resulting in reducing the generalization ability of the models and increasing the difficulty of crop yield forecasting at the early stages. In this study, the correlations between Sentinel-2 data (vegetation indices and reflectance) and yield data collected by combine harvester were investigated and a generalized multivariate linear regression (MLR) model was built and tested with data acquired in different years. It was found that the four-band reflectance (blue, green, red, near-infrared) performed better than their vegetation indices (NDVI, EVI, WDRVI and OSAVI) in wheat yield prediction. The optimum phenological stage for wheat yield prediction with highest accuracy was at the growing stages from the end of the flowering to the beginning of the filling stage. The best MLR model was therefore built to predict wheat yield before harvest using Sentinel-2 data acquired at the end of the flowering stage. Further, to improve the ability of the yield prediction at the early stages, three simple unsupervised domain adaptation (DA) methods were adopted to transform the reflectance data at the early stages to the optimum phenological stage. The winter wheat yield prediction using multiple vegetation indices showed higher accuracy than using single vegetation index. The optimum stage for winter wheat yield forecasting varied with different fields when using vegetation indices, while it was consistent when using multispectral reflectance and the optimum stage for winter wheat yield prediction was at the end of flowering stage. The average testing RMSE of the MLR model at the end of the flowering stage was 604.48 kg/ha. Near the booting stage, the average testing RMSE of yield prediction using the best MLR was reduced to 799.18 kg/ha when applying the mean matching domain adaptation approach to transform the data to the target domain (at the end of the flowering) compared to that using the original data based on the models developed at the booting stage directly (“MLR at the early stage”) (RMSE =1140.64 kg/ha). This study demonstrated that the simple mean matching (MM) performed better than other DA methods and it was found that “DA then MLR at the optimum stage” performed better than “MLR directly at the early stages” for winter wheat yield forecasting at the early stages. The results indicated that the DA had a great potential in near real-time crop yield forecasting at the early stages. This study indicated that the simple domain adaptation methods had a great potential in crop yield prediction at the early stages using remote sensing data.

Keywords: wheat yield prediction, domain adaptation, Sentinel-2, within-field scale

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Authors: Abdel-Monem Sayed Mohamed

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Lake Aswan is one of the largest man-made reservoirs in the world. The reservoir began to fill in 1964 and the level rose gradually, with annual irrigation cycles, until it reached a maximum water level of 181.5 m in November 1999, with a capacity of 160 km3. The filling of such large reservoir changes the stress system either through increasing vertical compressional stress by loading and/or increased pore pressure through the decrease of the effective normal stress. The resulted effect on fault zones changes stability depending strongly on the orientation of pre-existing stress and geometry of the reservoir/fault system. The main earthquake occurred on November 14, 1981, with magnitude 5.5. This event occurred after 17 years of the reservoir began to fill, along the active part of the Kalabsha fault and located not far from the High Dam. Numerous of small earthquakes follow this earthquake and continue till now. For this reason, 13 seismograph stations (radio-telemetry network short-period seismometers) were installed around the northern part of Lake Aswan. The main purpose of the network is to monitor the earthquake activity continuously within Aswan region. The data described here are obtained from the continuous record of earthquake activity and lake-water level variation through the period from 1982 to 2015. The seismicity is concentrated in the Kalabsha area, where there is an intersection of the easterly trending Kalabsha fault with the northerly trending faults. The earthquake foci are distributed in two seismic zones, shallow and deep in the crust. Shallow events have focal depths of less than 12 km while deep events extend from 12 to 28 km. Correlation between the seismicity and the water level variation in the lake provides great suggestion to distinguish the micro-earthquakes, particularly, those in shallow seismic zone in the reservoir–triggered seismicity category. The water loading is one factor from several factors, as an activating medium in triggering earthquakes. The common factors for all cases of induced seismicity seem to be the presence of specific geological conditions, the tectonic setting and water loading. The role of the water loading is as a supplementary source of earthquake events. So, the earthquake activity in the area originated tectonically (ML ≥ 4) and the water factor works as an activating medium in triggering small earthquakes (ML ≤ 3). Study of the inducing seismicity from the water level variation in Aswan Lake is of great importance and play great roles necessity for the safety of the High Dam body and its economic resources.

Keywords: Aswan lake, Aswan seismic network, seismicity, water level variation

Procedia PDF Downloads 367

Authors: Junjun Chen, Yingxiu Li

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The occupational well-being of school principals has played a vital role in the pursuit of individual and school wellness and success. However, principals’ well-being worldwide is under increasing threat because of the challenging and complex nature of their work and growing demands for school standardisation and accountability. Pressure is particularly acute in the post-pandemicfuture as principals attempt to deal with the impact of the pandemic on top of more regular demands. This is particularly true in Hong Kong, as school principals are increasingly wedged between unparalleled political, social, and academic responsibilities. Recognizing the semantic breadth of well-being, scholars have not determined a single, mutually agreeable definition but agreed that the concept of well-being has multiple dimensions across various disciplines. The multidimensional approach promises more precise assessments of the relationships between well-being and other concepts than the ‘affect-only’ approach or other single domains for capturing the essence of principal well-being. The multiple-dimension well-being concept is adopted in this project to understand principal well-being in this study. This study aimed to understand the situation of principal well-being and its influential drivers with a sample of 670 principals from Hong Kong and Mainland China. An online survey was sent to the participants after the breakout of COVID-19 by the researchers. All participants were well informed about the purposes and procedure of the project and the confidentiality of the data prior to filling in the questionnaire. Confirmatory factor analysis and structural equation modelling performed with Mplus were employed to deal with the dataset. The data analysis procedure involved the following three steps. First, the descriptive statistics (e.g., mean and standard deviation) were calculated. Second, confirmatory factor analysis (CFA) was used to trim principal well-being measurement performed with maximum likelihood estimation. Third, structural equation modelling (SEM) was employed to test the influential factors of principal well-being. The results of this study indicated that the overall of principal well-being were above the average mean score. The highest ranking in this study given by the principals was to their psychological and social well-being (M = 5.21). This was followed by spiritual (M = 5.14; SD = .77), cognitive (M = 5.14; SD = .77), emotional (M = 4.96; SD = .79), and physical well-being (M = 3.15; SD = .73). Participants ranked their physical well-being the lowest. Moreover, professional autonomy, supervisor and collegial support, school physical conditions, professional networking, and social media have showed a significant impact on principal well-being. The findings of this study will potentially enhance not only principal well-being, but also the functioning of an individual principal and a school without sacrificing principal well-being for quality education in the process. This will eventually move one step forward for a new future - a wellness society advocated by OECD. Importantly, well-being is an inside job that begins with choosing to have wellness, whilst supports to become a wellness principal are also imperative.

Keywords: well-being, school principals, quantitative, influential factors

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Authors: Anna Ghosh, Dominic Shields, Ceri McIntosh, Stephen Crank

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A 29-year-old male was a referral to the maxillofacial unit following a referral from his general dental practitioner via a routine pathway regarding a large periapical lesion on the LR4 with root resorption. The patient was asymptomatic, the LR4 vital and unrestored, and this was an incidental finding at a routine check-up. The patient's past medical history was unremarkable. Examination revealed no extra or intra-oral pathology and non-mobile teeth. No focal neurology was detected. An orthopantogram demonstrated a well-defined unilocular corticated radiolucency associated with the LR4. The root appeared shortened with the radiolucency between the root and a radio-opacity, possibly representing the displacement of the apical tip of the tooth. It was recommended that the referring general practitioner should proceed with orthograde root canal therapy, after which time exploration, enucleation, and retrograde root filling of the LR4 would be carried out by a maxillofacial unit. The patient was reviewed six months later where, due to the COVID-19 pandemic, the patient had been unable to access general dental services for the root canal treatment. He was still entirely asymptomatic. A one-year review was planned in the hope this would allow time for the orthograde root canal therapy to be completed. At this review, the orthograde root canal therapy had still not been completed. Interestingly, a repeat orthopantogram revealed a significant reduction in size with good bony infill and a significant reduction in the size of the lesion. Due to the ongoing delays with primary care dental therapy, the patient was subsequently internally referred to the restorative dentistry department for care. The patient was seen again by oral and maxillo-facial surgery in mid-2022 where he still reports this tooth as asymptomatic with no focal neurology. The patient's history was fully reviewed, and noted that 15 years previously, the patient underwent open reduction and internal fixation of a left angle of mandible fracture. Temporary IMF involving IMF screws and fixation wires were employed to maintain occlusion during plating and subsequently removed post-operatively. It is proposed that the radiolucency was, as a result of the IMF screw placement, penetrating the LR4 root resulting in resorption of the tooth root and development of a radiolucency. This case highlights the importance of careful screw size and physical site location, and placement of IMF screws, as there can be permeant damage to a patient’s dentition.

Keywords: facial trauma, inter-maxillary fixation, mandibular radiolucency, oral and maxillo-facial surgery

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Authors: Laura Kupers, Julie Piérard, Niki Cauberg

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The use of exposed concrete (sometimes referred to as architectural concrete), keeps gaining popularity. Exposed concrete has the advantage to combine the structural properties of concrete with an aesthetic finish. However, for a successful aesthetic finish, much attention needs to be paid to the execution (formwork, release agent, curing, weather conditions…), the concrete composition (choice of the raw materials and mix proportions) as well as to its fresh properties. For the latter, a simple on-site pass/fail test could halt the casting of concrete not suitable for architectural concrete and thus avoid expensive repairs later. When architects opt for an exposed concrete, they usually want a smooth, uniform and nearly blemish-free surface. For this choice, a standard ‘construction’ concrete does not suffice. An aesthetic surface finishing requires the concrete to contain a minimum content of fines to minimize the risk of segregation and to allow complete filling of more complex shaped formworks. The concrete may neither be too viscous as this makes it more difficult to compact and it increases the risk of blow holes blemishing the surface. On the other hand, too much bleeding may cause color differences on the concrete surface. An easy pass/fail test, which can be performed on the site just before the casting, could avoid these problems. In case the fresh concrete fails the test, the concrete can be rejected. Only in case the fresh concrete passes the test, the concrete would be cast. The pass/fail tests are intended for a concrete with a consistency class S4. Five tests were selected as possible onsite pass/fail test. Two of these tests already exist: the K-slump test (ASTM C1362) and the Bauer Filter Press Test. The remaining three tests were developed by the BBRI in order to test the segregation resistance of fresh concrete on site: the ‘dynamic sieve stability test’, the ‘inverted cone test’ and an adapted ‘visual stability index’ (VSI) for the slump and flow test. These tests were inspired by existing tests for self-compacting concrete, for which the segregation resistance is of great importance. The suitability of the fresh concrete mixtures was also tested by means of a laboratory reference test (resistance to segregation) and by visual inspection (blow holes, structure…) of small test walls. More than fifteen concrete mixtures of different quality were tested. The results of the pass/fail tests were compared with the results of this laboratory reference test and the test walls. The preliminary laboratory results indicate that concrete mixtures ‘suitable’ for placing as exposed concrete (containing sufficient fines, a balanced grading curve etc.) can be distinguished from ‘inferior’ concrete mixtures. Additional laboratory tests, as well as tests on site, will be conducted to confirm these preliminary results and to set appropriate pass/fail values.

Keywords: exposed concrete, testing fresh concrete, segregation resistance, bleeding, consistency

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Authors: Shyamani Hettiarachchi, Gopi Kitnasamy

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Background: The potentially high level of physical need and dependency experienced by children with cerebral palsy could affect the quality of life (QOL) of the child, the caregiver and his/her family. Poor QOL in children with cerebral palsy is associated with the parent-child relationship, limited opportunities for social participation, limited access to healthcare services, psychological well-being and the child's physical functioning. Given that children experiencing disabilities have little access to remedial support with an inequitable service across districts in Sri Lanka, and given the impact of culture and societal stigma, there may be differing viewpoints across respondents. Objectives: The aim of this study was to evaluate the psychometric properties of the Tamil version of the Cerebral Palsy Quality of Life for Children (CPQOL-Child) Questionnaire. Design: An instrument development and validation study. Methods: Forward and backward translations of the CPQOL-Child were undertaken by a team comprised of a physiotherapist, speech and language therapist and two linguists for the primary caregiver form and the child self-report form. As part of a pilot phase, the Tamil version of the CPQOL was completed by 45 primary caregivers with children with cerebral palsy and 15 children with cerebral palsy (GMFCS level 3-4). In addition, the primary caregivers commented on the process of filling in the questionnaire. The psychometric properties of test-retest reliability, internal consistency and construct validity were undertaken. Results: The test-retest reliability and internal consistency were high. A significant association (p < 0.001) was found between limited motor skills and poor QOL. The Cronbach's alpha for the whole questionnaire was at 0.95.Similarities and divergences were found between the two groups of respondents. The child respondents identified limited motor skills as associated with physical well-being and autonomy. Akin to this, the primary caregivers associated the severity of motor function with limitations of physical well-being and autonomy. The trend observed was that QOL was not related to the level of impairment but connected to environmental factors by the child respondents. In addition to this, the main concern among primary caregivers about the child's future and on the child's lack of independence was not fully captured by the QOL questionnaire employed. Conclusions: Although the initial results of the CPQOL questionnaire show high test-retest reliability and internal consistency of the instrument, it does not fully reflect the socio-cultural realities and primary concerns of the caregivers. The current findings highlight the need to take child and caregiver perceptions of QOL into account in clinical practice and research. It strongly indicates the need for culture-specific measures of QOL.

Keywords: cerebral palsy, CPQOL, culture, quality of life

Procedia PDF Downloads 341

Authors: Markus Bredel, Sindhu Nair, Hoa Q. Trummell, Rajani Rajbhandari, Christopher D. Willey, Lewis Z. Shi, Zhuo Zhang, William J. Placzek, James A. Bonner

Abstract:

Purpose: EGFR-targeted monoclonal antibodies (mAbs) provide clinical benefit in some patients with H&N squamous cell carcinoma (HNSCC), but others progress with minimal response. Missense mutations in the EGFR ectodomain (ECD) can be acquired under mAb therapy by mimicking the effect of large deletions on receptor untethering and activation. Little is known about the contribution of EGFR ECD mutations to EGFR activation and anti-EGFR response in HNSCC. Methods: We selected patient-derived HNSCC cells (UM-SCC-1) for resistance to mAb Cetuximab (CTX) by repeated, stepwise exposure to mimic what may occur clinically and identified two concurrent EGFR ECD mutations (UM-SCC-1R). We examined the competence of the mutants to bind EGF ligand or CTX. We assessed the potential impact of the mutations through visual analysis of space-filling models of the native sidechains in the original structures vs. their respective side-chain mutations. We performed CRISPR in combination with site-directed mutagenesis to test for the effect of the mutants on ligand-independent EGFR activation and sorting. We determined the effects on receptor internalization, endocytosis, downstream signaling, and radiation sensitivity. Results: UM-SCC-1R cells carried two non-synonymous missense mutations (G33S and N56K) mapping to domain I in or near the EGF binding pocket of the EGFR ECD. Structural modeling predicted that these mutants restrict the adoption of a tethered, inactive EGFR conformation while not permitting association of EGFR with the EGF ligand or CTX. Binding studies confirmed that the mutant, untethered receptor displayed a reduced affinity for both EGF and CTX but demonstrated sustained activation and presence at the cell surface with diminished internalization and sorting for endosomal degradation. Single and double-mutant models demonstrated that the G33S mutant is dominant over the N56K mutant in its effect on EGFR activation and EGF binding. CTX-resistant UM-SCC-1R cells demonstrated cross-resistance to mAb Panitumuab but, paradoxically, remained sensitive to the reversible receptor tyrosine kinase inhibitor Erlotinib. Conclusions: HNSCC cells can select for EGFR ECD mutations under EGFR mAb exposure that converge to trap the receptor in an open, constitutively activated state. These mutants impede the receptor’s competence to bind mAbs and EGF ligand and alter its endosomal trafficking, possibly explaining certain cases of clinical mAb and radiation resistance.

Keywords: head and neck cancer, EGFR mutation, resistance, cetuximab

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Authors: Tom Elias, Kiran G. Shirlal

Abstract:

Coastal erosion is one of the major issue faced by maritime countries, globally. More than 1200 km stretch of Indian coastline is marked eroding. There have been numerous attempts to impede the erosion rate and to attain equilibrium beach profiles. High cost and unavailability of natural rocks forced coastal engineers to find alternatives for conventional hard options like seawalls and groynes. Geosynthetic containment systems, emerged in the mid 20th century proved promising in catering coastal protection in countries like Australia, Germany and United States. The present study aims at reviewing Indian timeline of protection works that uses geosynthetic containment systems. Indian exploration regarding geosynthetic containment system dates back to early 2000s. Generally, protection structures use geosynthetics in the form of Geotubes, Geocontainers, and Geobags with Geotubes being most widely used in the form of submerged reefs, seawalls, groynes and breakwaters. Sand and dredged waste are used to fill these containment systems with calculated sand fill ratio. Reviewing the prominent protection works constructed in the east and west coast of India provides an insight into benefits and the difficulties faced by the practical installation. Initially, geosynthetic structures were considered as a temporary protection method prior to the construction of some other hard structure. Later Dahanu, Hamala and Pentha experiences helped in establishing geotubes as an alternative to conventional structures. Nearshore geotubes reefs aimed to attain equilibrium beach served its purpose in Hamala and Dahanu, Maharashtra, while reef constructed at Candolim, Goa underwent serious damage due to Toe Scour. In situ filling by pumping of sand slurry as in case of Shankarpur Seawall, West Bengal remains as a major concern. Geosynthetic systems supplemented by gabions and rock armours improves the wave dissipation, stability and reflection characteristics as implied in Pentha Coast, Odisha, Hazira, Gujarat and Uppada, Andhra Pradesh. Keeping improper design and deliberate destruction by vandals apart, geosynthetic containment systems offer a cost-effective alternative to conventional coastal protection methods in India. Additionally, geosynthetics supports marine growth in its surface which enhances its demand as an eco-friendly material and encourages usage.

Keywords: coastal protection, geotubes, geobags, geocontainers

Procedia PDF Downloads 148

Authors: Adesuwa Omorede, Karin Axelsson

Abstract:

The war and violence around the world today has brought a mass increase of forcibly displaced individuals to seek refuge in the European Union, where they have to leave their homes and restart a new life built on other cultural, social, economic and legal premises than they are used to. Since 2014, the EU has accepted to help with the crisis by providing protection and refuge, and countries like Germany, Hungary, Austria, and Sweden accepted around two-thirds of EU’s asylum seekers. In 2015 for instance, Sweden harbored large numbers of refugees, which lead to a drastic rise in population. This drastic rise brought an overwhelming challenge to Sweden since they needed to find quick and suitable solutions to accommodate these thousands of refugees. Further, it posed a challenge for Sweden to immediately tackle the problem of integrating the new arrivals in the labor market. With an unstable societal integration and little or no skills to connect to the workforce, these immigrants faced a shaky beginning, as they had to struggle with not just integrating into a new society but also to get suitable jobs. These uncertainties brought pressure on the immigrants, which drove a number of them to move from city to city seeking for a place and alternatives for their well-being, safe haven, and self-provision. As a result, they brought in their own skills, experiences, and cultural orientation into exploring and exploiting new opportunities and filling the gaps in their new environment. In so doing, immigrants contributing with multidisciplinary collaborations, insights, international relations and national growth through the exploitation of entrepreneurial opportunities. The study, seek to understand how these uncertainties led migrant entrepreneurs towards entrepreneurial activities. Furthermore, it contributes to understanding their processes towards exploring and exploiting opportunities for entrepreneurship as well as their role in contributing to local and national growth. To reach these aims, an inductive qualitative study was conducted using semi-structured interviews of several migrant entrepreneurs – both female and male – that took part in two different entrepreneurial projects in mid-Sweden. The first project was a business program for African women; the other was an entrepreneurship hub for immigrants. Both were focused on inspiring and coaching immigrants during their entrepreneurial process. An integrated part was to work with the participants’ entrepreneurial skills and abilities. In addition, archival documents were collected. The data was analyzed using content analysis for qualitative research. The study aims to contribute to the entrepreneurship literature by understanding the influences of cognitive and environmental factors towards entrepreneurial activities. This study also provides several suggestions for policymakers on how they can better integrate migrants into becoming contributors to the society.

Keywords: entrepreneurial intentions, entrepreneurial processes, migrant entrepreneurship, uncertainty

Procedia PDF Downloads 195

Authors: Farhina Haque, Chanyeop Park

Abstract:

The high efficiency, high field, and high power density provided by wide bandgap (WBG) semiconductors and advanced power electronic converter (PEC) topologies enabled the dynamic control of power in medium to high voltage systems. Although WBG semiconductors outperform the conventional Silicon based devices in terms of voltage rating, switching speed, and efficiency, the increased voltage handling properties, high dv/dt, and compact device packaging increase local electric fields, which are the main causes of partial discharge (PD) in the advanced medium and high voltage applications. PD, which occurs actively in voids, triple points, and airgaps, is an inevitable dielectric challenge that causes insulation and device aging. The aging process accelerates over time and eventually leads to the complete failure of the applications. Hence, it is critical to mitigating PD. Sharp edges, airgaps, triple points, and bubbles are common defects that exist in any medium to high voltage device. The defects are created during the manufacturing processes of the devices and are prone to high-electric-field-induced PD due to the low permittivity and low breakdown strength of the gaseous medium filling the defects. A contemporary approach of mitigating PD by neutralizing electric fields in high power density applications is introduced in this study. To neutralize the locally enhanced electric fields that occur around the triple points, airgaps, sharp edges, and bubbles, electrets are developed and incorporated into high voltage applications. Electrets are electric fields emitting dielectric materials that are embedded with electrical charges on the surface and in bulk. In this study, electrets are fabricated by electrically charging polyvinylidene difluoride (PVDF) films based on the widely used triode corona discharge method. To investigate the PD mitigation performance of the fabricated electret films, a series of PD experiments are conducted on both the charged and uncharged PVDF films under square voltage stimuli that represent PWM waveform. In addition to the use of single layer electrets, multiple layers of electrets are also experimented with to mitigate PD caused by higher system voltages. The electret-based approach shows great promise in mitigating PD by neutralizing the local electric field. The results of the PD measurements suggest that the development of an ultimate solution to the decades-long dielectric challenge would be possible with further developments in the fabrication process of electrets.

Keywords: electrets, high power density, partial discharge, triode corona discharge

Procedia PDF Downloads 200